Hey, Who's at the Controls? A Computer? That's Right

By SEWELL CHAN

Published: January 18, 2006

Without fanfare or ceremony -- and with no way for riders to notice -- two subway trains on the L line rolled out of the Rockaway Parkway station in Brooklyn just after midnight yesterday and became the first in the system's 101-year history to be controlled by computers.

The occasion was an important step, but only a baby step, in a $288 million project known as communications-based train control, which is intended to modernize the signaling system that guides train movements. New York City Transit, the largest arm of the Metropolitan Transportation Authority, began the project in 1999 after years of planning.

For now, only the two eight-car trains on the L line are being supervised by computers. On those trains, the operator is still applying the brakes and the accelerator but is obeying speed instructions on a computer display instead of wayside signals. If the operator fails to stop or moves the train too quickly, the computer will stop the train.

For now, the two trains are being supervised by computers only between midnight and 5 a.m. and on the segment of the L between Rockaway Parkway, the line's eastern terminus in Canarsie, and Broadway Junction, in East New York. Once the trains travel west past Broadway Junction, they revert to full human control.

By spring, if all goes well, the computer will fully operate the two trains, and the train operator's role will be limited to opening and shutting the doors, the traditional tasks of the conductor, and then pressing a button to start the train moving.

Over the next several months computerized operation will be expanded to more trains and more hours. Then the system will be expanded to the westernmost portion of the L line (from Eighth Avenue to Third Avenue, in Manhattan) and then to the rest of the line (from Third Avenue to Broadway Junction).

''It's a gradual implementation of technology,'' said Nabil N. Ghaly, chief signal engineer in the department of capital program management at New York City Transit. ''This is a major step for us. We expect the progress to continue, with more trains, then more hours, then more territory.''

Dr. Ghaly, an electrical engineer, said the new system would increase by nearly 20 percent the number of trains that can be operated at once on a line; at the height of the commuter rush, for example, 33 trains an hour might pass through a station, compared with today's 28.

Dr. Ghaly also said the new system was safer. ''This system continuously monitors the speed of the train, and it knows what the safe speed is,'' he said. ''Anytime there is a violation of the safe speed, the system takes over and applies the brake.''

The concept was designed by the Parsons Corporation, an engineering company; Arinc, a transportation communications company; and Booz Allen Hamilton, a consulting company. Siemens, another engineering concern, supplied the system. Computerized trains are used in San Francisco, London and Paris, but in New York the system has not been well publicized and is unfamiliar to most riders.

Last year, New York City Transit tried to remove the conductors from the L, arguing that their traditional role -- to open and shut doors and make announcements -- had become obsolete. The union that represents the conductors persuaded an arbitrator that the action was a contract violation, and the conductors were restored. (Other trains continue to operate without conductors, usually on short lines and at off-peak hours, in a program that began in 1996.)

The next line projected for modernization is the No. 7. Design for a new signaling system on that line is to be completed this fall, with a contract to be awarded next year, Dr. Ghaly said.